1. Field of the Invention
The invention relates to a fluid recovery system and, more particularly, two fluid recovery systems using a shredder in combination with a centrifuge.
2. Description of Related Art
Fluid recovery systems continuously remove liquid from lubrication-impregnated chips fabricated from metal and the like. Typically, these systems include a centrifuge which places a centrifugal force on the lubrication-impregnated chips sufficient to separate the liquid lubrication out of the chips. These systems are well known in the art and the teachings in U.S. Pat. Nos. 3,233,735, 3,366,318, and 3,850,814 are representative of such structures.
In several embodiments, a shredder is needed to reduce the size of the lubrication-impregnated chips prior to being spun by the centrifuge. The shredder shreds long strands of chips into smaller strands. The shredder also chips into smaller strands. The shredder also separates clumps of chips or strands of chips by reducing the mass of each individual entity so that each entity, a strand or chip, will be affected by the centrifugal force created by the centrifuge.
The shredder is usually an item which is added to the path through which the chips are processed. The shredder is operated independently of the centrifuge. Therefore, the shredder is equipped with a motor which is used exclusively to operate the shredder. The motor and transmission for the shredder increase the cost and space associated with the shredder. Additionally, the motors used to operate the shredders must be reversible so that the large masses which jam the shredders may be repositioned. Fly wheel assemblies, used to briefly increase the torque applied to the shredder elements, are cost prohibitive.
As with the shredder, the centrifuge is rotated by a motor dedicated thereto. Because the centrifuge is a large frustrum-shaped metal drum, its mass is great. The motor used to rotate the centrifuge must be capable of overcoming the inertia of this mass. Once the centrifuge is rotating, much less energy is required to maintain the rotational speed of the centrifuge. Therefore, much of the capacity of this motor is not used throughout the majority of its operating life.
Another inertial issue arises when the motor operating the centrifuge is turned off. Namely, the inertia possessed by the mass of the centrifuge maintains the rotational speed of the centrifuge long after the motor has turned off. This continued rotation is a safety hazard because it is rotating silently in an environment which is typically noisy and where human beings are wearing ear protection. Another problem associated with the continued rotation of the centrifuge is the excessive wear on bearings and parts associated therewith. Braking systems have been used to reduce the time the centrifuge is rotating. These systems, however, sharply increase the system cost and maintenance.